Natural theology: or, Evidence of the existence and attributes of the Deity

their substance, figure and position, manisestly faired to the formation of an image by the refraction of rays of light, at least as manisestly as the glasses and tubes of a dioptric telescope are suited to that purpose, it concerns not the proof which these afford of design and of a designer, than there may perhaps be other parts, certain muscles, for instance, or nerves, in the fame eye, of the agency or effect of which we can give no account; any more than we should be inclined to doubt, or ought to doubt, about the construction of a telescope, viz. for what purpose it was constructed, or whether it were constructed at all, because there belonged to it certain screws and pins, the use or action of which we did not comprehend. I take it to be a general way of infusing doubts and scruples into the mind, to recall to it its own ignorance, its own imbecility; to tell us that upon these subjects we know little; that little impersectly; or rather, that w.e know nothing properly about the matter. These suggestions so fall in with our consciousnesses, as sometimes to produce a general distrust of our faculties and our conclusions But this is an unfounded jealousy. The uncertainty of one thing, does not ne5 ceffarily
cessarily affect the certainty of another thing. Qur ignorance of many points need not suspend our assurance of a few. Before we yield, in any particular instance, to the scepticism which this fort of insinuation would induce, we ought accurately to ascertain, whether our ignorance or doubt concern those precise points upon which our conclusion rests. Other points are nothing. Our ignorance of other points may be of no consequence to these; though they be points, in various respects, of great importance. A just reasoner removes from his consideration, not only what he knows, but what he does not know, touching matters not strictly connected with his argument, i. e. not forming the very steps of his deduction: beyond these, his knowledge and his ignorance are alike irrelative.

CHAP

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i CHAPTER VI.

j „ THE ARGUxMENT CUMULATIVE.

Were there no example in the world of contrivance except that of the ej/etit would be alone sufficient to support the conclusion which we draw from it, as to the necessity of an intelligent Creator. It could never be got rid of: because it could not be accounted for by any other supposition, which did not contradict all the principles we possess of knowledge; the principles according to which, things do, as often as they can be brought to the test of experience, turn out to be true or false. Its coats and humours, constructed, as the lenses of a telescope are constructed, for the refraction of rays of light to a point, which forms the proper action of the organ; the'provision, ip. its muscular tendons for turning its pupil XO the object, similar to that which is given to the telescope by screws, and nport which power of direction ifr the eye, the exercise of its office as an optical instrument depends; the further provision for its desence, ! - G for

for its constant lubricity and moisture, which we see in its socket and its lids, in its gland for the secretion of the matter of tears, its outlet or communication with the nose for carrying off the liquid after the eye is washed with it; these provisions compose altogether an apparatus, a system of parts, a preparation of means, so manifest in their design, so exquisite in their contrivance, so successful in their issue, so precious and so infinitely beneficial in their use, as, in my opinion, to bear down all doubt that can be raised upon the subject. And what I wish, under the title of the present chapter, to observe, is, that, if other parts of nature were inaccessible to our enquiries, or even if other parts of nature presented nothing to our examination but disorder and confusion, the validity of this example would remain the fame. If there were but one watch in the world, it would not be less certain that it had a maker. If we had never in our lives seen any but one single kind of hydraulic machines yet,, if of that one: kind we understood the mechanism, and use, we ihould be as perfectly assured that it proceeded from the hand, and thought, and skill of a workman, as if we visited a museum of the arts,

and
and faw collected there twenty different kinds of machines for drawing water, or a thoufand different kinds for other purposes. Of this point each machine is a proof, independently of all the rest. So it is with the evidences of a divine agency. The proof is not a conclusion, which lies at the end of a chain of reasoning, of which chain each instance of contrivance is only a link, and of which, if one link fail, the whole falls; but it is an argument separately supplied by every separate example. An error in stating an example affects only that example. The argument is cumulative in the fullest sense of that term. The eye proves it without the ear; the ear without the eye. The proof in each example is complete; for when the design of the part, and the conduciveness of its structure to that design, is shewn, the mind may set itself at rest: no future consideration can detract any thing from the force of the example.